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Draco Galaxy Trio

Posted: 30 April 2021

Monday, 26 April 2021, was cloudy and very windy. Tuesday, 27 April, was cloudy with some periods of light rain (total 0.2"). Wednesday, 28 April, was also cloudy with some periods of rain (0.1"). The sky cleared on Thursday, 29 April, but the wind returned. The wind was forecast to decrease after sunset so I opened the observatory.

Open: Thursday, 29 April 2021, 1810 MST
Temperature: 84°F
Session: 1628
Conditions: Clear, breezy

12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece

iPhone 11 Pro Max

SYNCed the observatory clock to WWV time signals.

1819-1854 MST: relaxed on the observatory patio bench.

1855 MST: LX600 ON, StarLock OFF, High Precision OFF.

1908 MST: sunset. Calm now.

Slewed to the planets Mercury and then Venus, both very low in the western sky and behind some trees. No planets visible. 1915 MST: viewed Venus, 102X. 1945 MST: viewed Mercury, 102X.

1950 MST: High Precision ON.

Slewed to NGC5981, part of the Draco Galaxy Trio (NGC5981, NGC5982, and NGC5985). None of the galaxies were visible in the twilight sky. 1959 MST: NGC5982 and NGC5985, the brighter galaxies, were faintly visible, 102X.

2001 MST: back to relaxing on the bench to watch the stars comes out.

2004 MST: took these handheld iPhone 11 Pro Max photographs of the constellation of Leo high overhead while I was relaxing on the bench. They were taken with the iOS Camera app (Night Mode, 10 seconds, 1X and 2X respectively).


2020 MST: the Zodiacal Light was very bright in the western sky. I went back inside the observatory.

Viewed the Draco Galaxy Trio, 102X. NGC5981 (the edge-on galaxy) was faintly visible, NGC5982 (elliptical galaxy) was easy to see, and NGC5985 (spiral galaxy) was also easy to see.

Mounted the D850 DSLR at prime focus, focused on the star Arcturus, locked the 12" primary mirror, and slewed to NGC5982 (the middle galaxy).

2033 MST: StarLock ON.

Took two framing test images and then took six StarLock autoguided images of the Draco Galaxy Trio (5 minutes, ISO 12800, White Balance 5560K). This is one of the full-frame images.


One of the images had a satellite that passed directly infront of the middle galaxy. This is a stack (cropped) of the other five images (effective exposure 25 minutes) using Affinity Photo.

Draco Galaxy Trio (left-to-right:NGC5985, NGC5982, NGC5981)

2115 MST: StarLock OFF, High Precision OFF.

2120 MST: Viewed the Draco Galaxy Trio again, 102X. Nice view now against a dark sky.

Then viewed M83 (Southern Pinwheel Galaxy), 102X. Very nice view of the spiral arms.

Viewed Centaurus A (galaxy) and then Omega Centauri (globular cluster), 102X. Both were too low in the southeastern sky for a good view.

2132 MST: LX600 OFF.

2144 MST: took a Sky Quality reading using the Unihedron SQM-L.

Close: Thursday, 29 April 2021, 2146 MST
Temperature: 61°F
Session Length: 3h 36m
Conditions: Clear, SQM 21.25

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